2',3'-Dideoxyinosine-5'-Triphosphate

2',3'-Dideoxyinosine-5'-Triphosphate (ddITP) is a sugar modified nucleoside triphosphate, where the 2' and 3' hydroxyl groups are absent, resulting in chain termination. The inability of polymerases to extend from a dideoxy nucleotide causes the chain termination and is useful in a variety of biotechnology applications. ddITP is used in cycle sequencing, enzyme mechanistic studies and for producing RNA and DNA sequences that cannot be extended by polymerases or joined by DNA ligases. Another notable application that utilizes a primer terminated on the 3' end with a dideoxy modification is pyrophosphorolysis-activated polymerization (PAP) . This technique is valuable for the detection of rare mutations.